Perl's Data::Dumper shows objects instead of values

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 foreach my $row (1..$end) 
 { 
  foreach my $col (3..27 ) 
  { 
    # skip empty cells 
    next unless defined 
    $worksheet->Cells($row,$col)->{'Value'}; 

    # print out the contents of a cell  
    $var = $worksheet->Cells($row,$col)->{'Value'};     
    push @dates, $var;  

    print $var; #this prints the value just fine
  } 
 }  

my %hash;
$hash{'first'} = \@dates;
print Dumper \%hash; #This prints object information 

I am using the module OLE for Perl and every value I get from my worksheet and print $var then I get the expected value, but when I put everything into a hash it prints:

'first' => [
bless( do{\(my $o = 15375916)}, 'OLE::Variant'), 
bless( do{\(my $o = 15372208)}, 'OLE::Variant'),

And so forth. I must not understand something about hashes, because I'm really stumped here.

2

There are 2 answers

1
mob On BEST ANSWER

push @dates, $var pushes an OLE::Variant object onto your @dates array, while print $var calls the implicit OLE::Variant method to convert the object to a string.

If you also want @dates to just contain the underlying string values and not the objects themselves, say

push @dates, "$var";

which will stringify the date object before putting it into the @dates array.

1
rjray On

The values returned by the $worksheet->Cells($row,$col)->{'Value'} call are objects that are mostly C/C++ in nature, and Perl only has a handle on the object, represented by a memory location (which you see in the dump as a large integer). Many CPAN modules that wrap underlying C/C++ libraries behave the same way (XML::LibXML is on example that pops to mind). The short answer is, this is the object, and it is all you can see by means of Data::Dumper unfortunately. They are essentially blessed scalar references, and all operations on them are through methods, not through the actual value of the underlying reference itself.